A galvanometer has an internal resistance of 200 $\Omega$ and requires a current of 5.0 mA for full-scale deflection.What resistance should be connected in parallel with this galvanometer to make an ammeter that reads 10 A at full-scale deflection? A)0.10 $\Omega$ B)4.0 $\times$ 10⁵ $\Omega$ C)400 $\Omega$ D)0.20 $\Omega$ E)2.0 $\Omega$

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The correct answer is A because the resistance of the ammeter is given by the formula:Ra = (Ig / Ig - If) * Rgwhere:Ra is the resistance of the ammeterIg is the current at full-scale deflection of the ammeterIf is the current at full-scale deflection of the galvanometerRg is the internal resistance of the galvanometerSubstituting the given values into the formula, we get:Ra = (10 A / 10 A - 5.0 mA) * 200 ΩRa = 0.10 Ω

A Galvanometer Has an Internal Resistance of 200 Ω\OmegaΩ And Requires a Current of 5

A Galvanometer Has an Internal Resistance of 200 $\Omega$ And Requires a Current of 5